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Community occupancy models estimate species‐specific parameters while sharing information across species by treating parameters as sampled from a common distribution. When communities consist of discrete groups, shrinkage of estimates toward the community mean can mask differences among groups. Infinite‐mixture models using a Dirichlet process (DP) distribution, in which the number of latent groups is estimated from the data, have been proposed as a solution. In addition to community structure, these models estimate species similarity, which allows testing hypotheses about whether traits drive species response to environmental conditions. We develop a community occupancy model (COM) using a DP distribution to model species‐level parameters. Because clustering algorithms are sensitive to dimensionality and distinctiveness of clusters, we conducted a simulation study to explore performance of the DP‐COM with different dimensions (i.e., different numbers of model parameters with species‐level DP random effects) and under varying cluster differences. Because the DP‐COM is computationally expensive, we compared its estimates to a COM with a normal random species effect. We further applied the DP‐COM model to a bird data set from Uganda. Estimates of the number of clusters and species cluster identity improved with increasing difference among clusters and increasing dimensions of the DP; but the number of clusters was always overestimated. Estimates of number of sites occupied and species and community‐level covariate coefficients on occupancy probability were generally unbiased with (near‐) nominal 95% Bayesian Credible Interval coverage. Accuracy of estimates from the normal and the DP‐COM was similar. The DP‐COM clustered 166 bird species into 27 clusters regarding their affiliation with open or woodland habitat and distance to oil wells. Estimates of covariate coefficients were similar between a normal and the DP‐COM. Except sunbirds, species within a family were not more similar in their response to these covariates than the overall community. Given that estimates were consistent between the normal and the DP‐COM, and considering the computational burden for the DP models, we recommend using the DP‐COM only when the analysis focuses on community structure and species similarity, as these quantities can only be obtained under the DP‐COM. [ABSTRACT FROM AUTHOR]

Given the limited funds available, spatial prioritisation is necessary to help decide when and where to undertake conservation. One method for setting local scale priorities for conservation action is the landscape species approach which aims to identify priorities based on the needs of a small number of wide ranging species with large environmental impacts. Despite being used for the past decade by conservation organisations such as Wildlife Conservation Society, the effectiveness of the approach for representing a more comprehensive range of biodiversity has never been evaluated. Here we compare conservation priorities identified using a suite of landscape species ( n = 13) against those using many alternative sets of threatened or endemic species ( n = 7–88) to assess the applicability and suitability of the landscape species approach in a biologically diverse landscape (Greater Virunga Landscape, Uganda, Rwanda, and Democratic Republic of Congo, Africa). We defined the minimum area needed to conserve each species on the basis of the species’ range size. We found that prioritising for landscape species adequately conserves only 31 (35%) species, whereas prioritising for an equal number of endemic species, threatened species, or randomly sampled species adequately conserves 74%, 69% and 42% of species, respectively. We also found that prioritising for one taxonomic group (birds or plants) alone resulted in better surrogacy performance than the Landscape Species. These results question the underlying assumption of the landscape species approach, that managing threats to Landscape Species will also manage threats to all other species, as it is applied in the Greater Virunga Landscape. [ABSTRACT FROM AUTHOR]

The article focuses on a study which documented the mammal community of the Albertine Rift in East Africa. The Albertine Rift has been declared by the researchers as one of the biodiversity hotspots in Africa due to the high number of species and high levels of endemism. Three species of mammals new to science were documented including two species of shrews and one species of horseshoe bat.

The article focuses on a study which revised the horseshoe bats of the Rhinolophus maclaudi species group. Members of the group are located in the mountainous region of West Africa and the Albertine Rift, east of the Congo River with a major gap between the two recognized sub-groups. Two additional species within this species group were described from the Albertine Rift center of endemism in the eastern Democratic Republic of Congo.

Small forest fragments are common in anthropogenic landscapes in the tropics. These have conservation value if they provide habitat for threatened wildlife and maintain connectivity between larger habitats. Riverine forests have particular 'corridor' potential due to their linear shape, but are under-studied in many regions. We surveyed trees in riverine fragments in Bulindi, an anthropogenic landscape 25 km south of the Budongo Forest in western Uganda, to determine their condition and assess their value for wildlife, particularly endangered chimpanzees Pan troglodytes. We assessed tree composition, structure and diversity and compared results with a previous survey made in Budongo, the nearest main forest block. Riverine fragments were considerably less species-dense and species-rich than Budongo. Community composition differed markedly between sites and there was virtually no overlap in common species. Common trees in fragments were characteristic of East African swamp and groundwater forests (e.g. the palm Phoenix reclinata) and the dominant tree family was the Moraceae, members of which produce fleshy fruits attractive to frugivores (e.g. figs). Important fruit foods for chimpanzees differed between habitats. While basal area of important fruit trees was comparable, overall density was greater in fragments. Our data suggest the riverine fragments offer a relatively food-dense habitat for chimpanzees and other frugivores. Small riverine forests have little or no protection regionally and are being extensively logged and cleared for agriculture. Species logged for timber in Bulindi included important chimpanzee fruit trees. Unless conservation projects successfully reverse current trends, the value of the riverine corridors for maintaining connectivity between main forest blocks is limited. [ABSTRACT FROM AUTHOR]